Euel-feed mechanism tor internal-combustion engines



E. A. JOHNSTON.

FUEL FEED MECHANISM FOR INTERNAL comausnow ENGINES.

APPLICATION FILED APR. 18, I912. RENEWED APR. 7.19l3.

1 1 93,02 1 Patented Aug. 1, 1916.

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E. A. JOHNSTON.

FUEL FEED MECHANISM FOR INTERNAL COMBUSTION ENGINES.

APPLICATION FILED APR, 18. m2. RENEWED APR. 1.1913.

1 1 93,02 1 Patented Aug. 1, 1916.

3 SHEETS-SHEET 2.

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E. A. JOHNSTON.

FUEL FEED MECHANISM FOR INTERNAL COMBUSTION ENGINES.

APPLICATION FILED APR. 18, I912. RENEWED APR. 7, I913.

1 1 93,02 1 Patented Aug. 1, 1916.

3 SHEETSSHEET 3.

UNITED STATES PATENT OFFICE.

EDWARD A. JOHNSTON, OF CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS, TO INTERNATIONAL HARVESTER CORPORATION, A CORPORATION OF NEW JERSEY.

FUEL-FEED MECHANISM FOR INTERNAL-COMBUSTION ENGINES.

Specification of Letters Patent.

Patented Aug. 1, 1916 Application filed April 18, 1912, Serial No. 691,736. Renewed April 7, 1913. Serial No. 759,574.

To all whom it may concern:

Be it known that I, EDWARD A. JOHNSTON, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have inventedcertain new and useful Improvements in F uel-F eed Mechanism for Internal-Combustion Engines, of which the following is. a specification.

My invention relates'to fuel feed mechanism of the type wherein the charge forming device includes a governor controlled oil feeding pump, and it consists in improved means for controlling the stroke of the pump by the governor mechanism and simultaneously therewith the mixture throttling valve; the objects of my invention being to provide a mechanism that will be sensitive to variation in speed of the engine and quickly responsive in its operation of charge forming. I attain these objects by means of the mechanism illustrated by the accompanying drawings, in which Figure 1 is a side elevation of an internal combustion engine with one of the fly wheels removed and having my invention embodied in its construction; Fig. 2 is a side elevation of the charge controlling mechanism detached from the engine cyl inder; Fig. 3 is a side elevation, partly in section, of Fig. 2; Fig. 4 is a plan view of the pump controlling and mixture throttling mechanism; and Fig. 5 is a top plan view of Fig. 4-.

The same reference characters designate like parts throughout the several views.

1 represents an engine crank case having a crank shaft 2 journaled in bearings carried thereby; 3 the cam shaft driven from the crank shaft in any preferred manner; 1 the power cylinder having a cylinder head 5 secured thereto.

The governor mechanism may be any of the well-known centrifugal forms inclosed within a casing 6 actuated by the cam shaft and including a rock shaft 7 journaled in bearings carried by the casing and having a depending lever arm 8 secured to one end thereof.

9 represents the body of a mixing chamber, having a base portion 10 whereby it is secured to the cylinder head 5 by means of bolts 11, and a flange 12 at the upper end thereof whereby it is connected to the lower end of an air conduit 13.

14 represents a mixture throttling valve of the butterfly type secured to a rocking stem 15 ournaled in opposite walls of the mixing chamber at the lower end thereof, and having an arm 16 secured to one end thereof that is operatively connected with the lever arm 8 of the governor mechanism by means of a rod 17, and integral with arm 16 is an arm 18 that is connected with the rod 17 by means of an adjustable clip member 19 secured to said rod, and a tension spring 20 operative to yieldingly resist a rocking movement of thevalve stem by the governor mechanism.

21 represents a constant level Water feed cup secured to the side wall of the body of the mixing chamber, and includes an inlet pipe 22 communicating with a source of water supply (not shown), an overflow pipe 23 and feed nozzle 24 communicating with the body of the cup by means of the vertically arranged conduit 25 and controlled by a common form of needle valve mechanism 26, the feed nozzle being located above the mixture throttling valve.

27 represents a kerosene feed pipe that may be connected with a source of fuel supply (not shown) communicating with the lower end of a vertically arranged pump cylinder 28 that is provided with laterally extending wing portions 29 whereby the cylinder is secured to the body of the mixing chamber by means of bolts 30, the feed pipe being provided with a check valve 31 that closes against the pump cylinder.

32 represents a laterally arranged conduit leading from near the lower end of the cylinder toward the interior of the mixing chamber and connected with a fuel spraying device including a horizontally arranged conduit 33 carrying a check valve 34 that opens under pressure from the pump and permits fuel to flow into a vertically arranged chamber 35 Within the mixing chamber, having a spring-pressed valve 36 seated upon the lower end thereof that opens under a suction stroke of the engine, the valve being located above the water feed valve.

37 represents the pump piston, and 38 a common form of stufiing box at the upper end of the pump cylinder including a gland 39 through which the piston operates.

40 represents a piston operating rod having the upper end thereof secured to the upper end of the piston by means of nuts 41, the lower end of the rod being stepped upon one end of a vertical swinging lever 42, the opposite end of the lever being journaled upon a laterally arranged stud 43 secured to an ear member 44 integral with the body of the mixing chamber.

By means of the above arrangement, it is apparent that the flow of the fuel, air, and water to the combustion chamber is controlled by the governor controlled throttling valve.

45 represents a hardened steel contact member secured to the lower side of lever 42 that engages with a cam 46 carried by the stem 15 of the mixture throttling valve and rocking therewith.

47 represents a lever having arms 48 spaced apart in a manner to receive the lever 42 between them, the arms being journaled coaxially with the lever upon the stud 43.

49 represents a rocking bell crank lever journaled upon a stud 50 and secured to an arm 51 integral with the body of the mixing chamber and having one arm thereof operativeiy connected with an eccentric mechanism 52 actuated by the cam shaft 3, the remaining arm having a roller 53 journaled thereon that engages with lever 47 and operates as a wiper to swing the lever downward as the bell crank arm is rocked about its axis.

54 represents a laterally projecting ear member integral with the free end of lever 47, and 55 represents a vertically arranged tension spring having one end connected with said ear member and the opposite end thereof with a bracket member 56 secured to the air conduit 13, the spring being operative to swing the lever 47 in a direction opposite that caused by the operation of the bell crank lever 49, and 57 represents an adjustable screw carried by an ear member 58 integral with the body of the mixing chamber and having the lower end thereof adapted to contact with the ear member 54 in a manner to limit an upward swinging movement of lever 47.

59 represents a contact member carried by the lever 47 and adapted to engage with lever 42 and lift it and the pump piston operating rod upward, the rod and lever being moved in an opposite direction by means of a tension spring 60, having one end connected with the rod and the opposite end thereof with the lever 47 In operation the lever 47 is constantly operated by the bell crank lever 49 through a fixed distance and the lever 42 through a variable distance, determined by the position of the governor controlled cam 46, and the charge of oil injected into the mixing chamber is governed by the degree of downward movement of the pump piston as controlled by the degree of angular movement imparted to lever 42. The stroke of the ump being controlled by the governor through the cam 46, the quantity of fuel supplied to the mixing chamber and com bustion chamber is therefore governor-controlled. At the same time the throttling valve which controls the flow of fuel, air and water to the combustion chamber, is also governor-controlled. Thus it is seen that there is a relation between the simultaneously governor-controlled pump and throttling valve, in that a certain amount of fuel is pumped into the mixing chamber and is permitted to pass the throttling valve with other ingredients of the explosive mix ture in accordance with the load on the engine, or the fuel demanded by the engine under various operating conditions. Under light load conditions relatively small amounts of liquid fuel and air are demanded. For that reason I have the governor control the stroke of the pump to furnish only a relatively small amount of liquid fuel to mix with a relatively small amount of air, the effective vacuum within the mixing chamber or the effective suction for drawing in a charge of liquid fuel and air being controlled by the governorcontrolled throttling valve. As the load increases from light load, the governor permits a greater supply of liquid fuel and a greater supply of air. Water is also supplied under certain operating conditions. The governor thus controls the cooperating fuel pump and throttling valve to supply the required proportions of fuel and air of the explosive mixture to meet all operating conditions.

What I claim as my invention, and desire to secure by Letters Patent, is:

1. A fuel feed mechanism for internal combustion engines having, in combination, a vertically arranged mixing chamber communicating with the atmosphere and with an engine cylinder, a rocking mixture throttling valve including a valve stem journaled in the walls of said mixin chamber, an arm .secured to said stem an operative connections between said arm and the engine governor mechanism, a fuel feed pump carried by said mixing chamber and communicating with a source of liquid fuel supply and said chamber, said pump including a reciprocating piston, a piston lifting rod having one end connected with said piston, a primary swinging lever engaging with the opposite end of said rod in a lifting manner, said rod being yieldingly held in engagement with said lever by means of a spring mechanism, a secondary swinging lever adapted to engage with said primary lever in a manner to lift said rod, a spring operative to swing said secondary lever in a direction to lift said primary lever, means connected with a moving part of the engine and operative to positively move said secondary lever in an opposite direction, and a cam carried by said valve stem and operative to limit a swinging movement of said primary lever in one direction.

2. A fuel feed mechanism for internal combustion engines having, in combination, a mixing chamber communicating with the atmosphere and with an engine cylinder, a rocking mixture throttling valve including a valve stem journaled in the walls of said mixing chamber, an arm secured to said stem and operatively connected with the engine governor mechanism, a fuel feed pump carried by said mixing chamber and communicating therewith and with a source of liquid fuel supply, said pump including a reciprocating piston, means for imparting motion to said piston, said means including primary and secondary levers pivoted coaxially upon said mixing chamber, said secondary lever engaging with said primary lever in a manner to lift the latter, a piston lifting rod having one end stepped upon said primary lever and the opposite end thereof connected with said piston, a tension spring having one end connected with said rod and the opposite end thereof with said secondary lever, a tension spring having one end connected with a fixed part of the mechanism and the opposite end thereof with said secondary lever and operative to lift said lever, a bell crank lever pivotally mounted upon a fixed part of the mechanism and operatively connected with a moving art of the engine, said latter lever engaging with said secondary lever in a manner to depress the same, and a cam carried by said valve stem and operative to limit a swinging movement of said primary lever in one direction.

3. A fuel feed mechanism for internal combustion engines having, in combination, a mixing chamber communicating with the atmosphere and with an engine cylinder, a rocking mixture throttling valve including a valve stem journaled in the walls of said mixing chamber, an arm secured to said stem and operatively connected with the engine governor mechanism, a fuel feed pump communicating with a source of liquid fuel supply and with said mixing chamber, said pump including a reciprocating piston, means for imparting a variable length of stroke to said piston, said means including a cam carried by the stem of said rocking mixture throttling valve, a lever having one end pivotally connected with a fixed part of the mechanism, a bell crank lever journaled upon a fixed part of the mechanism and operatively connected with the engine governor mechanism and having one arm thereof in engagement with the opposite end of said first mentioned lever and o erative to impart motion thereto in one rection only, and a spring mechanism operative to move said lever in an opposite direction, means for regulating the degree of angular movement of said lever, a third lever carried by said first mentioned lever and operatively connected with said pump piston, the degree of angular movement of said third lever being controlled by said cam.

4. In an internal combustion engine, the combination of a governor, a pump, a throttling valve, and single means for controlling said throttling valve and the length of stroke of said pump by said governor.

5. In an internal combustion engine, the combination of a governor, a pump, a throttling valve, and means for simultaneously controlling said throttling valve and the length of stroke of said pump by said governor.

6. In an internal combustion engine, the combination of a pump, a member for reg lating the stroke of said pump, a throttling valve, and means for automatically and simultaneously controlling said member and said throttling valve.

7. In an internal combustion engine, the combination of a pump, a cam for regulating the stroke of said ump, a throttling valve, and a governor or controlling said cam and said valve.

8. In an internal combustion engine adapted to receive a combustible charge of fuel and air, the combination of a pump for supplying fuel, a throttling valve for controlling the flow of a mixture, and a overnor by means of which the stroke 0 said pump and movement of said valve are controlled to supply required proportions of fuel and air in said mixture.

9. In an internal combustion engine, the combination of a. fuel pump capable of having its stroke varied, a throttling valve and a governor by means of which sai pump and throttling valve are controlled to supply varied amounts of fuel and to vary the valve opening under different load conditions.

EDWARD A. JOHNSTON.

Witnesses A. L. GRooKs, LEO J. Fons'ran. 

